1. The tolerance of a Class A 50 mL transfer pipet is ±0.05 mL. A student uses an uncalibrated Class A transfer pipet to deliver a total of 300 mL of solution. What is the uncertainty in the delivered 300 mL? ± ______________ mL 2. Next, the student calibrates the pipet. The calibrated pipet delivers a mean volume of 49.994 mL with an uncertainty of ±0.005 mL. The student then uses the calibrated 50 mL pipet to deliver a total of 199.976 mL of solution. What is the uncertainty in the delivered 199.976 mL? ± _______________ mL

1. The tolerance of a Class A 50 mL transfer pipet is ±0.05 mL. A student uses an uncalibrated Class A transfer pipet to deliver a total of 300 mL of solution. What is the uncertainty in the delivered 300 mL? ± mL 2. Next, the student calibrates the pipet. The calibrated pipet delivers a mean volume of 49.994 mL with an uncertainty of ±0.005 mL. The student then uses the calibrated 50 mL pipet to deliver a total of 199.976 mL of solution. What is the uncertainty in the delivered 199.976 mL? ± _ mL

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter7: Statistical Data Treatment And Evaluation

Section: Chapter Questions

Problem 7.13QAP

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1. Calculate the experimental density of a salt solution and the percent error (same as relative error percent) using some or all the data given below. solubility of NaCl salt in water: 0.357 g/mLmass of empty graduated cylinder: 25.19g mass of graduated cylinder + salt solution: 30.47g total volume of salt solution: 4.98 mLtrue density of salt solution: 1.07 g/mL
1) Suppose you use your calibrated 25-mL pipet twice to deliver “50 mL" liquid, what is the actual total volume? What is the error in the final volume? 2) Suppose you use your uncalibrated 25-mL pipet to transfer liquid, what is the systematic error in the transferred volume? If you use it twice, what is the size if the systematic error in the total volume? My calibrated pipet had an average and standard deviation of 24.77 ml +/- 0.006 ml.
In order to calibrate a pipet, you obtain the following data: # of drops mL Trial 1 30 0.72 Trial 2 30 0.77 Trial 3 30 0.82 What volume in mL does your pipet deliver per drop?
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What is the relative error in the ppt of the following data if the accepted value is 70.05 M? 70.24 M, 70.22 M and 70.10 M
State whether the errors in (a)–(d) are random or systematic:a. A 25-mL transfer pipet consistently delivers 25.031 ± 0.009 mL.b. A 10-mL buret consistently delivers 1.98 ± 0.01 mL when drained from exactly 0 to exactly 2 mL and consistently delivers 2.03 mL ± 0.02 mL when drained from 2 to 4 mL.c. A 10-mL buret delivered 1.983 9 g of water when drained from exactly 0.00 to 2.00 mL. The next time I delivered water from the 0.00 to the 2.00 mL mark, the delivered mass was 1.9900 g. d. Four consecutive 20.0-L injections of a solution into a chromatograph were made and the area of a particular peak was 4 383, 4 410, 4 401, and 4 390 units.
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